Choosing wood for outdoor projects
Projects exposed to heat, cold, moisture, wind, dirt, and insects require durable exterior-grade lumber. The woods listed on this downloadable chart possess natural resistance to the elements because of chemicals or high density given to them by Mother Nature, or because they have been commercially treated with heat or man-made chemicals. Of course, few woods will last long outdoors without a suitable finish (Related Content).
Pressure-treated pine and fir sit at the top of the list for convenience and budget-friendliness as most every home center and lumberyard stocks them. If you don't want a pale green for your project, apply a coat of stain or paint.
More attractive species in the mid-price range include varieties of oak and cedar. They mill easily and join with glue or screws; but be sure to drill pilot holes to avoid splitting.
For utmost durability without chemical additives, choose black locust, osage orange, redwood, ipe, teak, or thermally modified woods. But ipe and teak are among the most expensive woods suitable for outdoor use. And local sources for thermally modified wood, osage orange, and black locust can prove difficult to find.
When selecting boards, look for those cut from specific parts of the log. For example, regardless of the species, in untreated woods, heartwood proves more durable than sapwood because it's denser and contains more natural decay-fighting chemicals. For treated lumber, the opposite is true: Sapwood more readily soaks in the chemicals, so it proves more durable than treated heartwood. Refer to the chart on next page for more specifics on selecting a wood. Species native to your region will be easier to find and generally more attractively priced.